I noticed that I have some upgrades available for mplayer, transcode and mjpegtools. Should I run these updates? Is there anything I need to worry about if I do? Do I need to run these upgrades on the MD's as well or just on the core?

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The error was: APT Error. Context: Package download failed, Unable to correct problems, you have held broken packages., Unable to correct problems, you have held broken packages., Unable to correct problems, you have held broken packages., :